Experts have issued warnings over the illness

All five of the babies were under three months old.

The cough, which is also known as whooping cough, is highly contagious, and can be particularly dangerous for babies and young children.

Caused by a bacterial infection in the lungs and breathing tubes, the ‘100 day cough’ can plague sufferers for weeks afterwards.

The first two months of 2024 saw a 70% increase in cases of whooping cough, with a confirmed 1,468 cases.

Amid the rise in cases, experts have issued warnings over the '100 day cough' and what symptoms to look out for.

The five main symptoms of whooping cough are:

• Coughing bouts lasting for a few minutes and are worse at night
• Coughs that make a “whoop” sound – a gasp for breath between coughs
• Difficulty breathing after coughs, which could lead to turning blue or grey in young infants
• Bringing up a thick mucus, which can lead to vomiting
• Turning very red in the face

These signs and symptoms can take seven to 10 days to show and are usually mild at first, meaning they can often be mistaken for a common cold.

UKHSA consultant epidemiologist Dr Gayatri Amirthalingam said, via WalesOnline: "Whooping cough can affect people of all ages but for very young infants, it can be particularly serious. However, vaccinating pregnant women is highly effective in protecting babies from birth until they can receive their own vaccines.

"Parents can also help protect their children by ensuring they receive their vaccines at the right time or catching up as soon as possible if they have missed any. If you're unsure, please check your child's red book or get in touch with your GP surgery."

The NHS advises people see their GP if they or their child have the symptoms of whooping cough, or have had a cough for more than three weeks that is getting worse.

If you or your child are having significant breathing difficulties, fits or signs of pneumonia call 999 or go to your nearest A&E.

Children under six months and people with severe symptoms will normally be admitted to hospital for treatment.

For more information about whooping cough, you can visit the NHS website here.

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